With the improvement and development of the technology, people have increased the enjoyment of material life and spiritual level, and never decreased, such that people hope to realize imagination and effect in immersive virtual reality via display devices. Therefor, how to display stereoscopic images or pictures in display devices is a target to be achieved by current technology.
FIG. 1 illustrates a timing chart of a power consumption of a backlight unit and an oscillator when a liquid crystal display displays a flat image according to prior art. When the oscillator is a high level signal, the backlight unit is a high level signal, too. That is, the backlight unit provides a light source to a panel, and the power consumption of the backlight unit is referred to as W1.
FIG. 2 illustrates a timing chart of a power consumption of a backlight unit and an oscillator when the liquid crystal display displays a stereoscopic image according to prior art. The frequency of oscillator during displaying the stereoscopic image is the same as the frequency of oscillator during displaying the flat image as shown in the FIG. 1. An image must display sequentially a right-eye picture and a left-eye picture when the liquid crystal display displays the stereoscopic image, such that it reduces a light emitting frequency of the backlight unit. In order to keep brightness of pictures, the backlight unit increases power of light sources. Therefore, the backlight unit provides a light source for the liquid crystal display during a high level signal, and a power consumption of the backlight unit is referred to as W2. It assumes that power consumption is in proportion to brightness of the light source, the power consumption of the backlight unit W2 during displaying the stereoscopic image is two times the power consumption of the backlight unit W1 during displaying the flat image.
For instance, when the liquid crystal display displays the flat image and the backlight unit provides a light source to a panel, the current to turn on the light source by the backlight unit is 120 mA. However, when the liquid crystal display displays the stereoscopic image and the backlight unit provides a light source to a panel, the current to turn on the light source by the backlight unit is 240 mA. The output current during displaying the stereoscopic image is two times the outputting current during displaying the flat image. That is, the output power is two times the original output power. In the other words, in the other conditions remain unchanged, the load current of original magnetic material is 120 mA, but the load current of magnetic material becomes 240 mA during displaying the stereoscopic image, such that it needs to choose magnetic materials of which the withstand current is 240 mA, which led to cost increasing and material waste.
Thus, a liquid crystal display is required to reduce the power consumption of a backlight unit when the backlight unit is turned on during displaying a stereoscopic image.